Improvement in artificial limbs



PATENT OFFICE.

AMASA A4. MARKS, OF NEW YORK, N. Y.

IMPROVEMENT IN ARTIFICIAL LIMBS.

Specification forming part of Letters Patent N0. 40,763, dated December1, 1863.

To @ZZ whom it may concer-7c: f Be it known that I, AMAsA A. MARKS, othe city, county, and State of New York, have invented certain new anduseful Improvements in the Manufacture of Artificial Limbs; and I dohereby declare that the following is a full and exact description'of thesame, reference being made to the accompanying drawings, and to theletters of reference marked thereon, in which- Figure 1 is a perspectiveview of a foot to be attached to the stump of an amputated leg; Fig. 2,a longitudinal vertical section of the same, and Fig. 3 a perspectiveview of a hand to be attachedto the stump of an amputated arm.

The ordinary construction of artificial limbs involves the use ofsprings,joints, pivots, &c. to such an extent that they are not onlyvery costly, but also very liableto get out of order by use. I proposeto obviate these objections by my improvement, which consists in makingthe wearing parts of the limbs-viz., the foot and hand-ol a compositionof spongerubber 7 and hard rubber, or of sponge-rubber and wood, thespongernbber being used to give to the toes, heel, and body of the footand to the lingers and body of the hand the requisite degree ofelasticity, (corresponding as near as possible to the natural movementsof the two members,) and the hard rubber or wood filling to give therequisite degree of s lidity to enable them to be fastened and securedto the wooden stumps that are to be fastened and secured to and upon theremaining stumps of the leg or arm to which they are to be applied. Bythis means l avoid the use of springs, pivots, joints, 8vo., that areordinarily employed for producing the movement of the foot and hand inordinary artificial limbs, and also avoid the great expense and wear,making the limbs cheaper and more durable. The body of the foot A and ofthe hand B is made of what is commercially known as sponge-rubber]7possessing great strength, combined with the requisite degree ofelasticity. They are made in proper molds, of such different sizes asmay be required. C in the foot and D in the hand is the filling of hard(or inelastic) rubber or of wood, as may be preferred, to which theattachment to the wooden stump of the leg or arm is made. In the lattercase the attachment is made by a ball-and-socket joint, so that the handmay be set to any required position and be secured there. In the formerit is made direct and permanent to the stump, so that the foot can becontrolled absolutely by the movement of the remaining part of thenatural leg of the wearer.

Ihe natural movement of the foot is more closely imitated by myimprovement than by any other before known, while at the same time thecumbrous, expensive, and delicate attachments ordinarily used to eii'ectthe same purposes are dispensed with. In regard to the hand, I onlypropose to make it as an articial show limb, one that will cover thedefect, in appearance, due to the loss of the real member, and whichwill yet, when grasped by another person, have a more natural feelingthan a rigid artificial one would have.

What I claim as my invention, and desire to secure by Letters Patent,is-

Making feet and hands for artificial limbs of sponge or soft rubber,combined with hard rubber or wood, as and for the purpose herein setforth.

A. A. MARKS.

Witnesses FRANCIS S. Low, CHARLES Low.

